Unable to send or receive messages and calls from a blocked number after unblocking
I blocked someone, but I unblocked them. Now neither of us can receive messages or phone calls from each other. How can this be fixed?
[Re-Titled by Moderator]
I blocked someone, but I unblocked them. Now neither of us can receive messages or phone calls from each other. How can this be fixed?
[Re-Titled by Moderator]
Check your iPhone settings
Go to Settings and turn on Airplane Mode, wait five seconds, then turn it off. Check Do Not Disturb. Go to Settings > Focus > Do Not Disturb and make sure it's turned off. Check for any blocked phone numbers.
If you can't make or receive calls on your iPhone - Apple Support

Can't send or receive message then try these steps first
If you can't send or receive messages on your iPhone, iPad, or ...

You may get better and prompt responses if you may kindly provide the iPhone Model that you have and the iOS version if it is known to you and re-post.

With the limited information that you have provided, It is hard to even guess the problems faced by you.
You may get faster and better responses to your query by --> Writing an effective Apple Support Commun… - Apple ...

Please re-post with detail so that someone else can help.
Unable to send or receive messages and calls from a blocked number after unblocking